This invention relates to so-called electronic article surveillance systems, and particularly to such systems which are especially useful in their application to stores in which the checking out of merchandise takes place via a multiplicity of check-out aisles.
Electronic article surveillance (and its acronym "EAS") is the general term which has become commonly used to designate a variety of techniques employed to electronically detect the unauthorized removal of merchandise from a store.
EAS is practiced by means of a variety of different detection systems. However, these systems all have in common two essential components. One component is some form of special security tag affixed to each piece of merchandise which is to be protected from unauthorized removal. The other component is some form of electronic equipment which is capable of detecting the proximity of one of the special security tags. For example, the tag may be provided with an electrical circuit which is configured so as to be resonant at a particular radio frequency, and the detecting equipment may be in the form of two antennas, one radiating electrical signals in a band of frequencies which includes said resonant frequency and the other receiving these signals. These antennas are positioned on opposite sides of a check-out aisle. When merchandise with such a tag attached passes between the antennas, the received signals are distorted by the tag's presence; electronic signal processing circuitry connected to the receiving antenna senses the distortion and triggers an alarm.
In the presence of such an EAS system, it obviously becomes necessary to distinguish between merchandise whose removal is authorized (e.g. because it has been paid for) and that which is not. The EAS system itself is not inherently capable of making that distinction. It causes an alarm when a security tag is detected, regardless of the authorized or unauthorized state of the article.
One way to deal with this situation has been to disable the tag at the time that the corresponding item of merchandise becomes authorized for removal. In the radio-frequency system example given previously, this can be accomplished either by physically removing the tag at the time the merchandise is properly checked out, or by electronically deactivating the tag at that time, so that its subsequent passage between the antennas ceases to be detectable by the EAS system.
An entirely different approach is to leave the security tag in place and undeactivated and provide two separate paths for exiting from the store, one for the authorized merchandise, and the other for the customer. The customer exit path leads through the EAS system (e.g. between the two radio-frequency system antennas), while the merchandise exit path does not. In practice, this involves providing a check-out aisle at one end of which the merchandise is deposited before the customer passes through the EAS system installed in the aisle. The customer then passes through that system on the way to the opposite end of the check-out aisle, whereas the merchandise is moved along the aisle on a path which parallels the customer's path but does not pass through the EAS system. The customer then retrieves the merchandise and leaves. In this way, any alarm from the EAS system is presumptively attributable to the presence of tagged merchandise is still in the possession of the customer, rather than having been properly checked-out. By such separation of paths, the distinction can readily be made between properly checked-out merchandise and any which is being removed (whether intentionally or not) without proper check-out.
In stores in which there are multiple check-out aisles, such as supermarkets which typically feature a row of several such aisles (sometimes as many as 10, 20, or even more) it has been the practice to install a separate EAS system in each aisle.
More recently, it has been proposed to substantially reduce the cost of using EAS systems to protect stores having multiple check-out aisles by establishing a traffic pattern in the check-out and exit areas which would make it possible to greatly reduce the number of separate EAS systems needed.
To that end, it has recently been proposed to dispense with the installation of separate EAS systems in the individual check-out aisles, and to install only a single EAS system, at a common store exit location, through which all customers must pass, after having passed through their respective check-out aisles and paid for their purchases.
This type of arrangement is proposed, for example in U.S. Pat. No. 4,583,083 issued Apr. 15, 1986.
Such a proposal is superficially very attractive, because it would save the cost of multiple EAS system installations. An EAS system currently costs on the order of several thousand dollars. Therefore, savings of multiples of that amount could be realized by that proposal, both in initial equipment and also in continued maintenance, updating, etc. Moreover, particularly in supermarkets, it is already conventional to provide a single passageway, crossing the outlet ends of the individual check-out aisles, and leading to a common exit door. It is at this common exit door that it was proposed to place the single EAS system.
Although attractive from the standpoint of reduced EAS system costs, that proposal also had some ramifications which significantly detract from its potential advantages. First, unlike in those (conventional) prior arrangements which have a separate EAS system in each check-out aisle, in the arrangement proposed in said U.S. Pat. No. 4,583,083 it is no longer possible to permit the customer to regain possession of the checked-out merchandise at the check-out aisle itself. If that were permitted, then the customer would again have possession of tagged merchandise when passing through the EAS system stationed at the common exit door. Therefore, an alarm would occur even though this merchandise had been properly checked out and thus authorized for removal from the store. Moreover, the presence of such authorized merchandise at the EAS-equipped exit would mask the potential presence of unauthorized merchandise. In other words, each exiting customer would create a false alarm; conversely valid alarms would be masked by these false alarms.
The cure for this problem seems rather obvious: provide some other way to transport this checked-out merchandise out of the store, and give it back to the customer only after the customer has passed through the single EAS system at the common exit door. Unfortunately, that is easier said then done. There are only two ways to perform the merchandise transport required. One is by store employees assigned to that task (that is the way proposed in said U.S. Pat. No. 4,583,083). The other is by mechanical equipment, such as conveyors and the like. The use of employees turns this into a labor-intensive situation, which can easily more than offset the savings due to the reduced number of EAS systems. For example, in a supermarket having 10 check-out aisles, the annualized savings from using only one EAS system at the exit door, rather than a separate one at each check-out aisle, could be on the order of $10,000. Even one additional employee needed to perform the merchandise transport function required by said U.S. Pat. No. 4,583,083 could easily offset that saving. In practice, one employee could not serve 10 aisles in this way, without creating serious delays in customer departures. Mechanical equipment, for transport without human intervention, would manifestly be still more costly.
Moreover, provisions would have to be made for reliably reuniting each customer with that customer's specific merchandise beyond the exit door. In a busy store, with any given customer's purchases often in several separate bags, this could easily lead to mass confusion and dissatisfaction.
Looked at from a different perspective, that proposed arrangement would deprive the store--especially the supermarket--of one of its more important economic advantages, which is that the customers, rather than store personnel or expensive machinery, perform virtually all merchandise handling and transport functions.
Thus, what superficially looked like a very attractive proposal in reality in fraught with problems, which threaten to nullify its practical usefulness.
Accordingly, it is an object of the present invention to overcome the drawbacks of the recently proposed arrangement discussed above.
It is another object to provide an arrangement which retains the cost saving of reducing the number of EAS systems relative to the number of check-out aisles, without creating the need for merchandise transport by store employees or by mechanical means.
It is still another object to provide such an arrangement which is highly flexible and adaptable to a variety of store exit traffic patterns.
It is still another object to provide such an arrangement which is simple and inexpensive to implement.
It is still another object to provide such an arrangement which requires minimal departures from currently conventional check-out structures and procedures.